Anyone who has achieved it knows that maintaining weight loss in the long term is an uphill battle. At the same time, the global weight loss industry is valued at US$224 billion and is expected to grow to US$405 billion by 2030.
One of the most frustrating aspects for many is the yo-yo effect of calorie restriction. Within 2 years, after 5 years it will be about 80%. This is often seen as a personal failure and can have long-lasting physical, emotional and psychological consequences.
But not all are pessimistic. Researchers at the Max Planck Institute for Metabolic Research (MPIMR) and Harvard Medical School have found that dieting induces profound changes in neural pathways in the brain, sending much stronger signals to nerves that mediate hunger. . Blocking these signals could help scientists develop better treatments for maintaining weight.
“People have mostly focused on the short-term effects of dieting,” said Henning Fenselau, an MPIMR researcher who led the study. “We wanted to see what changed in the brain over time.”
To do so, the researchers fed mice and monitored brain circuits, focusing on agouti-related peptide (AgRP) neurons in the hypothalamus, which are known to regulate hunger. Previous studies have shown that stimulating these neurons leads to a sharp increase in food consumption. They found that neuronal pathways to AgRP neurons were amplified when the animal was feeding and remained at that amplified level, resulting in extreme hunger signals, resulting in greater food intake and faster weight gain. I found
“This study advances our understanding of how the neural wiring diagram controls hunger,” said co-author Bradford Lowell of Harvard Medical School. “We had previously discovered a key set of upstream neurons that physically synapse and excite AgRP-starved neurons. We found that the physical neurotransmitter connections between two neurons are significantly increased by diet and weight loss, which leads to long-term excessive hunger.”
When researchers inhibited the connections between these neurons, AgRP activity was reduced and animals showed a more controlled response to food intake. Unsurprisingly, this significantly reduced weight gain.
“This may give us the opportunity to reduce the yo-yo effect,” says Fenselau. “In the long term, our goal is to find treatments that help maintain post-diet weight loss. We are continuing to explore ways to block it.”
This research cell metabolism.
Source: Max Planck Institute for Metabolism
